linux: 4.15 -> 4.15.1

pkgs/os-specific/linux/kernel/linux-4.15.nix

···
 with stdenv.lib;
 
 import ./generic.nix (args // rec {
-  version = "4.15";
+  version = "4.15.1";
 
   # modDirVersion needs to be x.y.z, will automatically add .0 if needed
   modDirVersion = concatStrings (intersperse "." (take 3 (splitString "." "${version}.0")));
···
 
   src = fetchurl {
     url = "mirror://kernel/linux/kernel/v4.x/linux-${version}.tar.xz";
-    sha256 = "0sd7l9n9h7vf9c6gd6ciji28hawda60yj0llh17my06m0s4lf9js";
+    sha256 = "1pxgs5wqmidwa5lz6q1m9gz6jyvhvlgy8r5bs48cm08b0vcwsvlq";
   };
 } // (args.argsOverride or {}))